Despite all of the negative comments, Works well! Rated 5 out of 5 stars

If you're a person who LOVES add ons, but has the memory usage to high, this add on is for you! Went from 400mb to 150mb just like that!


Saves ram, yet causes forefox to work awful, crushes the broswer as well Rated 1 out of 5 stars

I've been using this plugin for about two years, however since last firefox update, the browser started working really awful, although I have made all the tweaks (like enabling pipelining etc) to make it a beast...

since I used to like this add on I did not even consider it could be the issue...

after wasting about a week trying anything to revive firefox(I even switched to opera for a while) I decided to read a bit more about how memory fox worked...

although it saves memory it does not allow firefox to work properly(at least not on any of my PCs, have plenty of ram and everything).

Just uninstalled it and firefox is flying again (faster than Chrome itself) :)

Rated 1 out of 5 stars

It crashed when I try to activate it.

Also took my browser to a suspended web-page.

Can't recommend this as I kicked the bucket on spot. Bummer!

Waterfox 28.0 - 4/30/2014

Memory Fox тормозит, а не ускоряет Rated 2 out of 5 stars

Если раньше Memory Fox заметно ускорял работу FF? то сейчас в FF 28.0 только замедляет, особенно при закрытии страниц. Отключив Memory Fox закрытие вкладок и завершение работы FF (фактическое - в диспетчере задач, а не в закрытии самого окна программы) происходит почти мгновенно, а с включенным Memory Fox, требуется около одной минуты. Моя система - Win8.1x64, оперативной памяти - 8 Gb.

Bad Firefox and Flashplayer - IT IS MY MEMORY! Rated 5 out of 5 stars

Firefox 27.0.1
MemoryFox 7.4

I have been using this for a while now and over the time i have used it i can now comment on how it is.


I was sick and tired of having to close my browser periodically and empty the cache etc because both Firefox and Flashplayer decided that they were going to hog all my memory, and even when i closed tabs and only had one video on youtube playing the Memory counter would creep way back up. Now, this still happens, both Firefox and Flashplayer still want all of your memory, but this little add'on steps in and slaps them around and takes it back for you.

You can set the delay for MemoryFox to kick into action and rescue your memory (Memory Recovery) from 0 Minutes and 1 minute to 3 minutes. When you look at your Task Manager click on the processes tab and watch what happens to Firefox and Flashplayer, MemoryFox will take back from both Working Memory and Private Memory!

So this little add'on get a five stars for how good it works, and also because i can move the icon onto the Menu Bar and have the entire lower part of the screen free to display web pages.

Memory Fox Professional version Rated 4 out of 5 stars

Using "Free Memory Fox Professional version - Update as of 10-08-2013"

The third option on the Snapshot Options tab, "Check (ON) to perform [ Image Snapshot \ of [Sysinternals' (Process Explorer ) ]" is grayed out.

The video, for version , shows all three options available.

Memory use is now 1171M, which is not super low but is lower than it has been without Memory Fox.

I think it's working to reduce Firefox Memory use, and it seems like Firefox is working more fluidly, but that's a bit subjective.

Rated 5 out of 5 stars

i don't know what happened but since i installed this firefox is smooth...i also noticed have lots of standby memory is that a problem????

less memory usage, faster browsing Rated 5 out of 5 stars

since I started using this addon, firefox won't use more than 180-200 mbyte of RAM, it used to reach even 700-800 mbyte but not anymore with memory fox

Rated 5 out of 5 stars

Now my computer uses less memory. 10X

Rated 5 out of 5 stars

This is an amazing add-on!! I normally leave FF open for multiple days with a bunch of tabs and it gets to the point where FF lags so much that I just have to restart it. With this add-on I have had FF open for about 24 hours so far with not one single moment of lag. When I look in the task manager I notice a massive decrease in RAM usage, and the rate at which the RAM increases is cut down a lot!! This is a great add-on!! Thank you :)

Security issues Rated 2 out of 5 stars

I really like the idea behind this add on. But this tries to gain access to my security program (eset). It generated a log every 4sec. I went in and re enabled add-ons one at a time until I found it.Maybe it thinks it's using to much memory. Just not comfortable with that. Stars for the concept

Developer's Reply


Stop Memory Fox from logging by going to the options for Memory Fox and un-check the Logging option.

You should NOT choose the selection for 'Activate Memory Fox - For All Processes'.

All processes means exactly that! 32bit and not system or 64bit processes.

Even if you did select for all processes, there is a BLACK LIST to add any processes that you'd not like for Memory Fox to be applied for memory Workingset reduction.

This version of Memory Fox 7.4 is not for 64bit processes, only a 32bit version of ESET would only be effected at that. Your system must be for 32bit Windows if MMF is touching the ESET application when using memory Workingset reduction for All Processes.

64bit ESET would require for Memory Fox to Enable Privileges to be Elevated for access to reduce its Workingset memory, of which, MMF version 7.4 does NOT have. This action is only available in Memory Fox Professional.

Using the selection of 'Activate Memory Fox - Browser Only' will not touch any other 32bit process.

ESET, is my primary prevention system for all of my development environments.


Memory Fox professional is good Rated 5 out of 5 stars

From my previous reply you suggested me to install professional one ( i bought a new 64bit machine ) , this is decreasing the flash memory and other processes memory also . Its Very good , No problems as of now . I hope there wont be any issues in future of page swapping , high cpu usage etc

This user has 2 previous reviews of this add-on.

Useless Rated 1 out of 5 stars

All this addon does is to shift bytes around. On the surface it looks like reducing the memory use. However, the commit size of the process does not change. At best, it does not do anything harmful. At worst, it forces your system to swap more.

See for a more detailed analysis.

Developer's Reply

Some users have asked about the statement, "However, the commit size of the process does not change."

Commit charge, is an allocation request controlled by the said Process which is instantiated by VirtualAlloc[Ex] using MEM_COMMIT flag, and is the amount of virtual ( Private Bytes ) memory reserved by the operating system for said process. Not accessible by other external processes, i.e. Memory Fox.

Memory Fox, as I stated in the header description of the add-on, "Attempting to reduce both Browser and Flash RAM Memory usage". Memory Fox makes a request from the working set memory manager to calculate how many pages ( non-active or orphaned ) can be removed from the working set, of your machine's RAM. This trimming allows other applications access to more available RAM memory for their needs. There may be upon this action a reduction, of the Commit size, if that orphaned page is no longer available such as a hosting tab removed or redirected to new webpage content such that the virtual allocation has not been removed or modified by the browser process. Windows Memory Manager works very efficiently but it's the available RAM memory that most application need to run of which becomes the most concern for the average user. This is why the I use the Memory Fox addon personally.

For those looking for a ( reliable ) and a ( clear ) Windows Memory Core explanation with definitions from a Microsoft Professional with a thorough Technical understanding explaining Windows' Memory Management, then there's a great resource book from a Microsoft Fellow, Dr. Mark Russinovich’s Windows Internals Part 1 & Part 2.

Additionally, Dr. Mark Russinovich’s ( RamMap ) application which is part of ( Microsoft's Windows Sysinternals Suite ) incorporates and provides ( user ) a menu within RamMap the ability to execute the same API call methods, for the same executions that provided reduction for orphaned memories of the Memory WorkingSet that the addon Memory Fox provides dynamically while using Firefox.


Rated 5 out of 5 stars

It works very well.

It works!!! Rated 5 out of 5 stars

I dont know how he does it, but it works on my firefox. Now I downloaded Memory Fox pro for my Windows. Thanks.
Normally my FF uses about 480 MB of Ram, now it is about 230 MB on the same tasks.

It works, but... Rated 5 out of 5 stars

How does the timer works? or what it does? the pro version has no timer? what is the better time option?

Developer's Reply

I'm not sure why you think either version, MF 7.4 or MFP doesn't have a timer, because both do. The options in both are pretty clear about timed function actions.

The default options for both MF 7.4 or MFP are very aggressive for their timed functioning actions, in each version. You may want to increase their default timed functioned actions.

If you need any additional information please email at and I'll follow up with an answer to any other questions.


I have to re-activate it too Rated 5 out of 5 stars

I'm using win7, FF21. I have to activate it everytime I start FF. It's little annoying. Btw, I clear cookies when I close FF.

Update : after a couple of times reactivate, it's active permanently

Works Rated 4 out of 5 stars

Good work - It cuts the memory usage for FF, but I notice on 32 bit FF 21 on Win XP, I have to "activate" it for the browser every time I run firefox. Is there a way to do this automatically, to have it activate every time firefox starts?


Developer's Reply

I'm not sure why you're having to re-activate Memory Fox. I went back to test download and installation of Memory Fox 7.5 on WinXP and once the Memory Fox is activated followed by closing the browser and re-instantiating the Firefox browser it launches the active setting of Memory Fox. I even rebooted and activated the Firefox browser with the same results as expected.

p.s. I have only one other active add-on for Firefox running with Memory Fox 7.4 and that's Session Manager. No other addons are installed.


It works but why do we need it????? Rated 4 out of 5 stars

Here is what I don't get:
1. I'm a vanilla FFX user.
2. the M-F author him/her self says it was never meant to be a permanent solution.
3. but it really works.
4. when I leave FFX running overnight with perhaps 8 mostly-text tabs
a. without M-F, despite setting cache to 10MB and seeing 200MB in the W7 Task Manager when I go to bed, I see 750MB when I get up the next morning.
b. with M-F set for FFX only, same scenario, same tabs, FFX shows up with 100MB the next morning, stays around 150MB during the day, and drops to around 90MB when I minimize FFX.
5. There is something wrong with FFX memory management.
6. There is something wrong with the FFX development group's handling of FFX's memory management.
7. I use FFX because it sticks to its promise not to keep trying to sell me something and it doesn't make my life difficult if I don't do it their way, like GDrive does if you don't use Chrome.
8. the years-long, constantly bitched about, memory hog issue remaining unresolved shows that you get what you pay for.
9. maybe it's time for a good $5 browser that doesn't do constant version changes, actually works, and doesn't have a million add-ons that no one uses anyway.
10. here's my $5.

Amazing! Rated 5 out of 5 stars

I was skeptical at first, but this add-on really does work. I am not sure about using this for all Windows processes, but it works amazingly for Firefox. I will be testing it with Palemoon x64 next but it looks very promising.